There is no denying the importance of filtration in the modern age. Medical filters can safeguard sterile environments, like operating rooms, by keeping out harmful pathogens and bacteria. Filters in vehicles make them more efficient. And with government regulations and environmental concerns, the filtration market is undeniably on a path toward continued growth.
The following is part three in a three-part series in International Filtration News considering key market trends within the filtration market. Part one considered the overall filtration market, drivers and size (IFNIssue 4 2021, pages 46-47). Part two offered a deeper look at the market for air filtration applications and technology (IFNIssue 5 2021, pages 46-47). And this third and final part of the series examines liquid filtration.
Liquid filtration is more than just water; liquid filters are also employed over a wide variety of fluids and applications. Liquid filtration applications tend to be concerned with the filtration of either aqueous or hydrocarbon fluids. As with the air filtration industry, the liquid filtration market captures a wide variety of end uses.
INDA has segmented the liquid filtration category into filters used, in tonnage order, for:
Liquid filtration based on nonwoven media is generally not considered an absolute method of purification because particles of 1 μm or less in size can pass through the media. In many applications where sub-micron contaminants are present, further separation is required.
Membrane- and nanofiber-based filtration and separation processes employ a membrane or nanofibers layered onto a nonwoven support, which increases the strength and improves the particle-retention capacity. Some of these membranes are so thin and fragile that they can only be produced by directly being coated onto the nonwoven carrier’s surface.
Unlike air filtration, the mechanisms of liquid filtration and separation are equally used and none of the applications dominate the field of solid/liquid separation. Replaceable filter elements are used in many filter applications. Two of the most common types using nonwovens are liquid bag filters (similar to air filtration baghouse filers) and cartridge filters, in addition to nonwovens being used as a membrane medium. One of the biggest uses of nonwoven filter media in liquid filtration is in cartridge filters, both in transportation, industrial applications and consumer water applications (water filters and swimming pool/spa filters). Cartridge filters make use of membrane, nonwoven, string wound, metal and carbon filters.
The most common fibers used in liquid filtration are polypropylene (PP), polyethylene (PE), polyester (PET), polybutylene terephthalate (PBT), nylon, glass, and cellulose.
The largest category depends upon the unit of measurement. The liquid food and beverage processing filtration end uses consumed a third (37%) in area of the nonwoven material, while transportation accounted for the greatest in tonnage, accounting for just over a third (38%) of the tonnes in 2019, and in terms of nonwoven media value transportation is the largest accounting for 38% (Figure 1).
Below is the North American growth outlook (2020–2024) for each of the categories, in a simplified format, followed by a brief summary for each.
++++ Healthcare
+++ Transportation
++ Food and Beverage Processing
++ Industrial/Manufacturing
+ Water
Demand for liquid filters is as varied as the end uses, though some of the more common drivers are:
The liquid filtration market, like the air filtration market, is indeed a diverse one with seemingly endless categories. The various drivers and developments have resulted in the North American liquid filtration market consuming an ever-greater amount of nonwoven material having expanded 4.1% annually in weight and 4.0% in volume through the historical period (2014–2019). This growth will continue through the forecast period (2020–2024), as reported in INDA’s North American Nonwovens Industry Outlook, 2019-2024, report.
The North American Nonwovens Supply report is one of three INDA member-publications produced by INDA’s Market Intelligence and Economic Insights Group. For additional information on these publications and other INDA member benefits, please visit www.inda.org/indamembers/index.html.
International Filtration News is owned by INDA, Association of the Nonwoven Fabrics Industry (inda.org).